title: Field seasonal influenza vaccine effectiveness: evaluation of the screening method using different sources of data during the 2010/2011 French influenza season.
abstract: Thanks to the screening method, we estimated among target groups the 2010/2011 field vaccine effectiveness (FVE) against laboratory confirmed influenza cases seen in general practice. We also compared the values of FVE estimations obtained by using three sources of the population vaccination coverage (VC) based on three different methodologies: (1) administrative data from the main social security scheme (Caisse Nationale d'Assurance Maladie des Travailleurs Salariés--CNAMTS) covering about 85% of the French population, (2) a cross-sectional national telephone survey in the general population, and (3) a declarative survey in the population seen in a one-day general practitioner (GP) consultations. The FVE estimates among target groups were stratified by age (< 65 y old with reported chronic illness; ≥65 y old and overall). Using the VC of the CNAMTS, the FVE of the 2010/2011 seasonal trivalent vaccine against laboratory confirmed infection with any influenza virus was 59% (95% Confidence Interval, 17 to 81). It was 85% (17 to 99) and 50% (-16 to 80) for A(H1N1)pdm09 and B influenza infections, respectively. The values of FVE using the influenza VC obtained in a sample of the general population and of the population of GPs' patients were 73% (45 to 87) and 82% (63 to 92), respectively. We estimated a moderate influenza FVE in preventing confirmed influenza viruses in target groups by using the VC of the CNAMTS. We also observed that the screening method generates FVE values dependent on the choice of the source of VC and thus should be used cautiously.
authors.affiliation: INSERM; U707; Paris, France; Laboratoire de Virologie; EA 7310 Université de Corse; Corte, France; UPMC Univ Paris 06; UMR S 707; Paris, France.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Falchi
authors.forename: Cecile
authors.initials: C
authors.lastname: Souty
authors.forename: Marie-Lise
authors.initials: ML
authors.lastname: Grisoni
authors.forename: Anne
authors.initials: A
authors.lastname: Mosnier
authors.forename: Thomas
authors.initials: T
authors.lastname: Hanslik
authors.forename: Isabelle
authors.initials: I
authors.lastname: Daviaud
authors.forename: Laurent
authors.initials: L
authors.lastname: Varesi
authors.forename: Solen
authors.initials: S
authors.lastname: Kerneis
authors.forename: Fabrice
authors.initials: F
authors.lastname: Carrat
authors.forename: Thierry
authors.initials: T
authors.lastname: Blanchon
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003625:Data Collection / Q000379:methods; D005260:Female; D005602:France; D006801:Humans; D007223:Infant; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines
keywords: general practitioners; influenza; target groups; vaccination coverage; vaccine effectiveness